Addendum: My mother was kind enough to remind me of Space Camp (1986) which probably falls more in the early childhood sweet-spot than BIG (1988). Yes, I read the Space Camp book, memorized the Space Camp script and wanted to become an astronaut for a good 3 years. How could I forget Space Camp? But just so that my taste isn't put into question - please consider the talent involved w/ this film: http://www.imdb.com/title/tt0091993/